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Re: Another stack approach in the Am29000


>>>>> "Doug" == Doug Girling <girling@cs.sfu.ca> writes:

    Doug> FWIW, stepping into the Wayback Machine (or at least
    Doug> "Computer", May 1977), one of the HP minis (the HP 3000) had
    Doug> 4 internal registers which formed the top 4 stack elements.
    Doug> As new things were pushed into R0, R3 was pushed into real
    Doug> memory, and vice versa.  Adding a bigger "stack cache" would
    Doug> probably help the algorithmic performance, but would need to
    Doug> be balanced against the overhead of flushing the stack cache
    Doug> on interrupts and context switches (i.e., where one changes
    Doug> the stack being used).

Not really a suprise, given the influence that Forth, RPN, and stacks
had already taken on HP.  After all, they introduced the HP-29
calculator that was a close to hand-held Forth as it got back then.

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